[AMDGPU] Disable hasVALUMaskWriteHazard for GFX12 (llvm#78187)

Author: jayfoad

llvm/lib/Target/AMDGPU/GCNSubtarget.h

@@ -1146,7 +1146,7 @@ class GCNSubtarget final : public AMDGPUGenSubtargetInfo,
 
   bool hasForceStoreSC0SC1() const { return HasForceStoreSC0SC1; }
 
-  bool hasVALUMaskWriteHazard() const { return getGeneration() >= GFX11; }
+  bool hasVALUMaskWriteHazard() const { return getGeneration() == GFX11; }
 
   /// Return if operations acting on VGPR tuples require even alignment.
   bool needsAlignedVGPRs() const { return GFX90AInsts; }